Hoping to examine clang's performance, I attempted a Release build of LLVM + clang. After 'make update' from my llvm directory to update to revision 75115:

llvm[1]: Compiling Alarm.cpp for Release build
llvm[1]: Compiling Atomic.cpp for Release build
llvm[1]: Regenerating LibDeps.txt.tmp
llvm[1]: Updated LibDeps.txt because dependencies changed
llvm[1]: Checking for cyclic dependencies between LLVM libraries. Circular dependency between *.a files: libLLVMAsmPrinter.a libLLVMCodeGen.a libLLVMSelectionDAG.a
llvm[1]: Building llvm-config script.
cat: /Users/rp/Desktop/llvm/tools/llvm-config/FinalLibDeps.txt: No such file or directory
make[1]: *** [/Users/rp/Desktop/llvm/Release/bin/llvm-config] Error 1
make: *** [all] Error 1

This is on OS X 10.5.7. The error persists after 'make clean'. A Debug build is normal.

Robert P.

It works for me on 10.5.7 with:
gcc version 4.0.1 (Apple Inc. build 5484)

Please go into tools/llvm-config and use "make ENABLE_OPTIMIZED=1 VERBOSE=1". That should show you how the dependency generation script is running, it takes a -why option. Please send me the output off-list (it's large) and I'll see if I can help.